Neurophysiologic disorders developed in three patients after discontinuation of transdermal fentanyl (TDF) at a daily dose of 0.6 mg (2.5 mg per a patch), although direct removal of a 2.5 mg patch is permitted by the manufacturer as the formulation has the lowest fentanyl content among all the commercially available patch formulations. These observations indicate that the discontinuation of TDF carries a risk for developing withdrawal symptoms even when using a 2.5 mg patch. To avoid such adverse events, we considered the necessity of gradual reduction in the daily fentanyl requirements. For this purpose, we covered part of the application surface of the patch with an insulating tape, and then increased the covered area in a stepwise manner. There were no apparent withdrawal signs during the procedure described above.